Our present modern way of life imposes more and more demands on products used for food, feed and pharmaceutical purposes, body care, etc. In this context, there is a continuous need for products which
have reduced calorific values, PA1 have a low fat content, PA1 have an increased fibre content, PA1 have a beneficial effect on intestinal and cutageneous microflora, PA1 have a lower sugar content, PA1 do not cause dental caries, PA1 possess physiologically functional characteristics. PA1 gamma inulin with molecules that have a very specific DP between 50 and 63, as described in WO 87/02679; PA1 inulin I 2255, I 3754 and I 2880 which have an av. DP which is significantly higher than the av. DP of the native inulin from which they are prepared, respectively native chicory, dahlia and Jerusalem artichoke (Sigma, USA) and which are non-food graded. PA1 fibruline LC (Warcoing, Belgium) a chicory inulin with PA1 an average DP which is significantly higher than the average DP of native inulin; PA1 an inulin composition which is significantly free of low molecular monosaccharides, dissacharides and oligosaccharides; and PA1 a refined fractionated inulin which is significantly free of impurities such as colourings, salts, proteins and organic acids; and PA1 an end product which is free of technological aids such as solubility affecting products. PA1 an av. DP which is significantly higher than the av. DP of the native polydisperse carbohydrate composition; PA1 significantly free from low molecular monomers, diomers and oligomers; PA1 significantly free of impurities chosen among the group consisting of colourings, salts, proteins and organic acids; PA1 significantly free of technological aids, such as solubility affecting products. PA1 diameter comprised between 1 and 100 .mu.m, preferably between 5 and 70 .mu.m, more preferably between 6 and 60 .mu.m, PA1 radial symmetry, double breaking and perpendicular fade cross under polarised light. PA1 the preparation of a metastable solution of a native polydisperse carbohydrate composition, PA1 a directed crystallisation of said metastable solution, PA1 a separation of the particles obtained after the crystallisation, PA1 a washing of the separated particles, PA1 possibly a drying of the washed particles, PA1 possibly a chemical or enzymatic treatment of the carbohydrates.
It is known that various carbohydrates, including fructans such as inulin, can fulfill these demands and can therefore be valuable ingredients for food products, functional food or feed, OTC and pharmaceutical products, cosmetic products etc.
It is known that e.g. native inulin can be obtained by industrial methods (F. Perschak, Zukerind.115, (1990), p.466). Through hot water extraction, an inulin-containing extract is separated out from tuber or root cuttings taken from inulin-containing plants. This extract is then demineralised and decolorized. RAFTILINE.RTM. chicory inulin ST is a commercially available product which contains native chicory inulin (Tiense Suikerraffinaderij, Belgium).
These inulin extracts are in fact a mixture of polymer molecules of various chain lengths.
A polydisperse carbohydrate composition such as e.g. inulin can be characterised by the chain length of the individual molecules (the degree of polymerisation or DP), and also by the percentage distribution of the number of molecules of a particular chain length, as well as by the average degree of polymerisation (av. DP).
A native polydisperse composition retains the molecular structure and the polydispersity pattern of the product as separated from its original source.
The degree of polymerisation of native chicory inulin molecules is between 2 and 60, the av. DP is around 11. The percentage distribution of the molecule fractions is approximately 31% for DP 2-9, 24% for DP 10-20, 28% for DP 21-40 and 17% for DP&gt;40 respectively. Native inulin from dahlias with an av. DP of 20 contains a significantly smaller share of oligofructoses and double the quantity of molecules with a chain length of DP&gt;40. Native Jerusalem artichoke inulin on the other hand contains extremely few molecules with DP&gt;40, only about 6%. The oligomer fraction DP&lt;10 accounts for approximately half of the molecules of the native polydisperse inulin of Jerusalem artichoke.
The polydispersity pattern of e.g. fructans strongly depends not only on the original production source from which the fructans are obtained (e.g. in vivo synthesis with plants or microorganisms or in vitro synthesis with enzymes), but also on the point of time at which the polydisperse compositions are extracted (e.g. plant harvest time, the action time of enzymes, etc.). The manner in which the polydisperse compositions are extracted likewise plays a role.
In addition, extracted native polydisperse compositions frequently contain a significant amount of other products such as e.g. monosaccharides and disaccharides such as glucose, fructose and saccharose and impurities such as proteins, salts, colourings, organic acids and technical aids such as solubility affecting products.